US1816020A

US1816020A - Automatic stop governor

Info

Publication number: US1816020A
Application number: US296832A
Authority: US
Inventors: Frank A Meyer
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1928-08-01
Filing date: 1928-08-01
Publication date: 1931-07-28
Anticipated expiration: 1948-07-28

Description

July 28, 1931.

F. A. MEYER AUTOMATIC STOP GOVERNOR Filed Aug. 1, 1928 WITNESS ATTORNEY Patented July 28, 1931 UNITED STATES PATENT OFFICE mean: A. MEYER, or Noawoon, PENNSYLVANIA, AssIsN'oR T WESTINGHOUSE ELEC- rare at mmurscruame COMPANY, A CORPORATION or rnnnsytvanra AUTOMATIC s ror eov'aaNoR Application filed August 1, 1928. Serial No. 296,832.

My invention relates to an automatic stop governor for a prime mover, and it has for its object to provide apparatus of the character designated which shall be simple, and alsoreliable in operation.

Another object is to provide an automatic overspeed stop governor which may be set without stopping the,prime mover, and a further object is to provide means for testing such a governor at a speed less than the overspeed for which it is set, without first shuttin down the prime mover.

nother object of the invention is to provide an automatic overspeed stop governor of the hydraulic or fluid pressure type.

Afurther object is to provide an automatic stop governor which shutsoli the supply of motive fluid upon failure or predetermined diminution of the fluid pressure at the inlet of an impeller for a fluid pressure governor. In accordance with my invention, I provide an element subjected to fluid pressure varymg as a function of the speed of the prime mover and bias said element in op osition to the fluid pressure by a constant orce, such as the force of gravity of a number of weights The amount of said force is such as to exceed or equal the force of said fluid pressure until a predetermined overspeed is exceeded, when said element is effective to shut oil the supply of motive fluid to the prime mover.

The above and other objects are effected by my invention, as will be apparent from the following description and claims taken in connection with the accompanying drawing, forming a part of this application, in which: I The single figure is a diagrammatic view of my automatic stop governor controlling the throttle valve of a prime mover parts thereof eing shown in section. Pteferring now to the drawing in detaiL-I' show my novel governor applied to a prime of the casing 11 su ortin a the shaft. 'rheshfr i 10 his mounted directly thereon and in an impeller housing 15. The impeller provides a fluid pressure which varies as the square of the speed of the prime mover. The

bearing 12 for an impeller 14:

of a piston a fragment of,

disposed withfluid which is used to provide this pressure is preferably lubricating oil which is also used for lubricating the bearin 12.

Motive fluid for the prime mover, hereinafter referred to as steam, is supplied thereto through a throttle valve 16 and a governor valve 17. The governor valve 17 is controlled and operated by a fluid pressure governor 18, having a piston 19 disposed in a cylinder 20.

The piston is operatively connected to the valve 17, and is biased to open the valve b a spring 20. The piston 19 is also subjected to the pressure developed by the impeller 14, which is transmitted thereto through a conduit'21, and which acts on the iston in opposition to the spring 20 and to close the valve 17.

Upon increase in speed, the increased oil pressure moves the piston 19 to decrease the valve opening 17, and upon a decrease in speed, the decreased pressure permits the spring 20 to move the piston 19 for increased valve opening.

It will be apparent that this form of governor for the valve 17 is shown merely for example, and that any type of speed governor may be used, or that a governor may be omitted.

At 23 I show a reservoir for supplying oil to the impeller 14. Oil from the reservoir 23 flows by gravity to an ejector 24, which is motivated by oil pressure transmitted throu h a conduit '25 from the impeller 14, and w ich supplies the oil at a lower pressure to the inlet of the impeller through a conduit 26. The conduit also supplies oil to the bearing 12. I

' The throttlevalve 16 is operated by a throttle valve operating mechanism 28 consisting 29 connected to the throttle valve, a cyliiider 30,11 spring 31, and a screw-thread ed stem 32. A passage 33 is provided in the piston 29 ,for providing communication between the upper and lower ends of the cylinder 30. The upper end of the passage is adapted to be covered by the lower end of the stem 32. Fluid pressure is supplied through a conduit 34 to the lower end of the cylinder 30 to actuate the piston 29 in valve opening direction, and a drain condiut 35 I communicates with the cylinder'30 above the i "so piston 29 and conveys the oil drained thererom to the reservoir 23. A restricted orifice 27 is interposed in the conduit 34 to limit the flow of fluid therethrough.

The valve operating mechanism 28 is controlled by my novel automatic stop governor 36, which will nowbe described. This governor includes a casing 37 having a cylindrical bore 38, a second cylindrical. bore 39 and a third cylindrical bore 40'. Disposed within the housing 37 is an element 41, which has a piston 42 in the cylindrical bore 39, a sleeve portion 46 extending therefrom, the end of which fits in the cylindrical bore 40, and

piston portions

43, 44 and 45 carried by the sleeve 46 and fitting in the bore 38. The sleeve portion 46 is provided with an annular row of ports 47 above the piston portion 43, a second row of ports 48 between the piston portions 43 and 44, and a third row of ports 49 between the piston portions 44 and 45.v Thecasing 37 hasa port 50 communicating with the impeller 14 through a conduit 51, and a port 52 communicating with the conduit 34. The casing 37 is also provided with ports 54 and 55 communicating with the drain conduit 35.

Extending through theupp'er end of the a casing 37 is a stem 56, on the upper end of which isformed a disc 57 adapted to carry a plurality of weights 58.

Disposed within the sleeve portion 46 is a valve member 59, having piston portions '60, 61 and 62. The lower end of the valve member 59 is secured to a piston 63 which is biased downwardly by a compression spring 64.

The piston 63 is biased upwardly, however, by the pressure of the fluid supplied to the impeller 14 through the conduit 26, which pressure is conveyed to .the lower end of the casing 37 through a conduit 64'.

A chamber '65 is formed between the piston portion 45 and a shoulder 66 which connects the

cylindrical bores

40 and 38. A conduit 67 communicates with the chamber 65 and also with the conduit .51, and-interposed in the conduit 67 is a hand valve 68, by means of which the supply of fluid under pressure 1 to'the. chamber 65 may be controlled. A small orifice 65' is formed in the sleeve 46 to perm t a restricted escape of fluid from'the chamber 65. A pressure gauge 69 communicates with the conduit 67 and indicates the pressure in the chamber 65. i A conduit 70, communicating with the conduit 51, is provided for supplying fluid pressure from an auxiliary source in starting the prime mover.

The operation of the.,above described apparatus is as follows The parts are shown in the position of normal operation, in which the pressureof the oil supplied to the impeller is sufficient to raise the piston 63 against the spring 64, and in which the pressure developed by the impeller is not sufiicient to raise the 42. In this position the piston portion 60 is disposed-immediately above the port 47 and the piston portion 44 is disposed below the port 52. Fluid pressure from the conduit 51 is therefore transmitted through the port 47,.

the'ports 48. the port 52, theconduit 34 and the orifice 27 to the throttle valve operating mechanism 28 to retain the same in open position.

Assume now that the prime mover exceeds a predetermined over-speed. .The weights 58 are so adjusted that atsuch times the impeller r pressure on the piston 42 overcomes the force of gravity of the weights and the eleinent'41,

and raises the piston 42. The pistonportion 6O thereupon covers the ports 47 and cuts off further supply of fluid pressure to the throttle valve operating mechanism. The piston portion 44 also moves upwardly above the port 52, placing the latter in communication with the drain port 54.

The oil in the throttle valve operating mechanism is free, therefore, to flow-through to effect a rapid closing of the throttle valve. 4

When the prime mover speed is restored to normal, the element 41 falls by force of gravity to its normal position, in which position fluid under pressure is conveyed to the throttle valve operating mechanism but escapes through the passage 33 without having any effect on the piston 29 until the hand wheel 32' is operated to lower the stem-32. The orifice 27 restricts the flow of fluid at this time to revent a loss of pressure in the conduit 51.

en it is desired to test the automatic stop governor and the throttle valve operating mechanism, at normal speed or any speed below the predetermined overspeed, the hand valve 68 is slowly opened to admit fluid un der pressure from the conduit 51 to the chamber 65. The pressure in said-chamber builds up and acts onthe piston portion 45 until'the element 41 moves upwardly to trip the valve operating mechanism. The pressure at which. the element 41 moves may be deter- .mined from the gauge 69, from which may be .In case of failure of oil pressure in the conduit 26, which supplies oil to the impeller 14,

the spring 64 forces the piston 63 and the valve member 59 downwardly. The piston 125. Thelow pressure trip operates as follows:

60., befoie, covers the ports 47 and cuts ofi the supply-of fluid pressure, .and the piston.

portion 61 moves below the ports 49, thereby placing the ports 52 in communication with the drain conduit 35 through the

ports

48, 49 and 54. The pressure in the cylinder 30 is released, as in the case of overspeed, and the throttle valve operating mechanism is tripped to close the throttle valve.

Upon restoration of the minimum oil pressure in the conduit 26, the piston 63 and the valve member 59 are moved upwardly to normal position and a restricted flow of oil is again supplied to the throttle valve operating mechanism. The stem 32 may then belowered and raised to again open the throttle valve.

From the above description, it will be apparent that. I have provided an automatic stop overspeed governor, which may be set without stopping the prime mover, by adding to or removing from the weights 58 on the disc 57. It will also be noted that the governor automatically resets itself, except that when testing it is necessary to close the valve 68.

An advantage of my novel governor is that it may be placed at any desired location, since it is hydraulically connected'to the apparatus with which it cooperates.

A further advantage is that the force opposing the governing force remains constant,-

and does not increase as in the case of spring force. Hence, when the predetermined overspeed is exceeded and theelement 41 begins to move, it continues to do so without further increase in speed.

The low pressure trip of my automatic stop governor provides a special protection for the fluid pressure governor, which increases the fluid admission with decrease in fluid pressure. In case of failure or abnormal drop in pressure of fluid sup-plied to the impeller, the pressure supplied to the governor would be correspondingly decreased and admit an excessive amount of motive fluid. The low pressure trip guards against such a possibility by closing the throttleivalve.

VVhile- I have shown niy invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications Without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set "forth in the appended claims.

What I claim is:

1. The combinationewith a prime mover and a throttle valve therefor, of mechanism for operating said throttle valve, means pro viding a fluid pressure varying as a function pressure and adapted to control said valve operating mechanism to close the throttle valve upon a predetermined pressure, means for applying fluid pressure to an additional area of surface of said element to effect movement thereof at a pressure on the first-memtioned area of less than the predetermined pressure, and means for indicating the pressure on said additional area.

2. The combination with a prime mover and a throttle valve therefor, of means for operating the throttle valve, means providing a fluid pressurevarying with the speed of the prime mover, an automatic stop governor responsive to saidfiuid pressure and adapted to control the throttle valve operating means to efi'ect complete closing thereof, means for adjusting said governor to operate at a predetermined pressure, and means independent of said adjusting means forefiecting operation of said governor at a pressure less than the predetermined pressure when testing the governor;

3. The combination with a prime mover having a throttle valve and a governor valve controlling the admission of fluid thereto, of means providing a fluid pressure varying as a function of the speed of the prime mover, means providing a supply of fluid to said means, a governor responsive to said pressure for regulating the governor valve, and means responsive to said supply for effecting complete closing of said throttle valve.

4. The combination with a prime mover having a throttle valve and a governor valve controlling the admission of fluid thereto, of means providing a fluid pressure varying as a function of the speed of the prime mover, means providing a suppl of fiuid to said means, a governor responsive to said pressure for regulating the governor valve, and means responsive to the pressure of the fluid su plied and for effecting complete closing of t e throttle valve.

5. The combination with a prime mover having a throttle valve and a governor valve controlling the admission of fluid thereto, of means providing a fluid pressure varying as a function of the speed of the prime mover, means providing a supply of fluid to said means, a governor. responsive to said pressure for regulating the governor valve, and means for eiieoting complete closing of the throttle valve upon failure of said supply.

In testimony whereof, I have hereunto subscribed my name this 27th day of July, 1928.

FRANK A. MEYER.

cumrlcm or common.

Patent'No. 1,816,020. Granted July H31, t0

. It is hereby certified that error sppears' in the printed specification or the above" numbered patent requiring correction as follows: Page 3, line 119. insert the following as claim 6 r 7 6. The combination with a prime mover and a throttle valve therefor, of mechanism for operating said throttle valve, means providing a-fluid pressure varying as a function .of the speed of'theprime mover, an automatic stop governor including an element having an area of surface suhjected to said flluiftlipre' eiand adapted to control said valve operating mechanism tgeloae ithe throttle valve upon a predetermined pressure, aad meansifbr appl'yjing fluid pressure to an additional area of surface of ssid-elemeptftoeffectmovement thereof at a pressure on the first-mentioned amal ofiilea than the predeterminedv pressure.

and that the said Letters Patentshouldi be read with this correction therein'that the same may conform to the record.v Pf the case in the Patent 0ffiee.

sealed this 6th' as; j-joember. A. 1 1931.

MLJ. Moore,

(Seal) Aetinz Commissioner of Patents.